

A127890


Largest ndigit righttruncatable prime.


3




OFFSET

1,1


COMMENTS

For a variant see the Howard reference.  Alexander R. Povolotsky, Dec 23 2007
Righttruncatable means that the integer part of successive divisions by 10 always yields primes (or zero).  M. F. Hasler, Nov 07 2018


REFERENCES

Toby Howard, "Magic Pi  The Magic of Numbers", PC Advisor magazine, May 1998.


LINKS

Table of n, a(n) for n=1..8.
I. O. Angell and H. J. Godwin, On Truncatable Primes, Math. Comput. 31, 265267, 1977.
Jens Fehlau, 73939133  Probably the Most Interesting Prime Number [Part 1] and [Part 2], Flammable Maths videos (2020).
Index entries for sequences related to truncatable primes


PROG

(PARI) A127890=vector(8, n, p=concat(apply(t>primes([t, t+1]*10), if(n>1, p))); p[#p]) \\ M. F. Hasler, Nov 07 2018


CROSSREFS

Cf. A024770, A050986, A127889.
Sequence in context: A104094 A220382 A036950 * A198973 A127859 A014293
Adjacent sequences: A127887 A127888 A127889 * A127891 A127892 A127893


KEYWORD

base,nonn,fini,full


AUTHOR

Ray Chandler, Feb 04 2007


STATUS

approved



